udp_*

Note: Deprecated. The udp_* tables are deprecated and will be removed in a
future release.

There are three system tables, all having the same columns:

udp_now is an external table whose data files are stored in
$MASTER_DATA_DIRECTORY/gpperfmon/data.

udp_tail is an external table whose data files are stored in
$MASTER_DATA_DIRECTORY/gpperfmon/data. This is a transitional table
for UDP statistical data that has been cleared from udp_now but has not
yet been committed to udp_history. It typically only contains a few
minutes worth of data.

udp_history is a regular table that stores historical UDP statistical
metrics. It is pre-partitioned into monthly partitions. Partitions are automatically
added in two month increments as needed. Administrators must drop old partitions for the
months that are no longer needed.